The present invention relates to triazolopyridazines as inhibitors of tyrosine kinases, including c-Met. Triazolopyridazines have been reported with useful therapeutic properties: U.S. Pat. No. 5,278,161 and US 2003181455 report triazolopyridazines as renin inhibitors; U.S. Pat. No. 6,355,798 reports triazolopyridazines as GABA inhibitors and GABAA receptor ligands respectively; WO 2005002590 and US 2005096322 report triazolopyridazines as mediating increases in bone mass; US 2004192696 reports triazolopyridazines as useful for treating or lessening the severity of a disease or condition. Academic laboratories have reported experiments with triazolopyridazines in the following: Science of Synthesis (2002), 12, 15-225, Heterocycles (2003), 61, 105-112, Heterocycles (2002), 57(11), 2045-2064, Journal of Heterocyclic Chemistry (1998), 35(6), 1281-1284, and Tetrahedron (1999), 55(1), 271-278.
Also of note are U.S. Pat. No. 4,810,705; DE 2222834 (equivalent U.S. Pat. No. 3,823,137); DE 2147013 (equivalent, U.S. Pat. No. 3,919,200); DE 2113438; DE 2030581 (equivalent U.S. Pat. No. 3,823,137); DE 1670160 (U.S. Pat. No. 3,506,656); DE 1545598 (equivalent U.S. Pat. No. 3,483,193); DE 2161587; DE 4309285; WO 2004021984; US 2004147568; JP 63199347; WO 1999037303; U.S. Pat. Nos. 6,297,235; 6,444,666; WO 2001034603; WO 2004017950; CA 2132489; WO 2004058769; US 2004192696 WO 2003074525; WO 2003032916; Japanese Patent Application Number 62-147775; U.S. Pat. No. 4,260,755; WO 2002012236; EP 464572; EP 404190; EP 156734; WO 2005002590; WO 2003074525; JP 63310891 and El Massry, Abdel Moneim; Amer, Adel, “Synthesis of new s-triazolo[4,3-b]pyridazines,” Heterocycles (1989), 29(10), 1907-14; Amer, Adel; El Massry, Abdel Moneim; Badawi, Mohamed; Abdel-Rahman, Mohamed, M.; El Sayed, Safaa A. F., “Synthetic reactions and structural studies of heterocycles containing nitrogen. Part 14. Dehydration of 2-(2-arylethyl)-2-hydroxy-4-oxopentanoic acids and their hydrazones to form heterocycles,” Journal fuer Praktische Chemie/Chemiker-Zeitung (1997), 339(1), 20-25; Legraverend, Michel; Bisagni, Emile; Lhoste, Jean Marc, “Synthesis of s-triazolo[4,3-b]pyridazine C-nucleosides (1),” Journal of Heterocyclic Chemistry (1981), 18(5), 893-8; Albright, J. D.; Moran, D. B.; Wright, W. B., Jr.; Collins, J. B.; Beer, B.; Lippa, A. S.; Greenblatt, E. N., “Synthesis and anxiolytic activity of 6-(substituted-phenyl)-1,2,4-triazolo[4,3-b]pyridazines,” Journal of Medicinal Chemistry (1981), 24(5), 592-600; How, Pow-Yui; Parrick, John, “Thermal cyclization of pyridazinylhydrazones to give s-triazolo[4,3-b]pyridazines and pyridazmo[2,3-a]benzimidazole,” Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry (1972-1999) (1976), (13), 1363-6; Lundina, I. B.; Frolova, N. N.; Postovskii, I. Ya.; Bedrin, A. V.; Vereshchagina, N. N., “Synthesis and study of the antitubercular activity of 2-(5-nitro-2-furyl)vinyl derivatives of pyridazine and s-triazolo[4,3-b]pyridazine,” Khimiko-Farmatsevticheskii Zhurnal (1972), 6(4), 13-17; Sircar, Ila, “Synthesis of new 1,2,4-triazolo[4,3-b]pyridazines and related compounds,” Journal of Heterocyclic Chemistry (1985), 22(4), 1045-8; Bratusek, Urska et al., “The synthesis of N-phthaloyl-azatryptophan derivatives,” Acta Chimica Slovenica (1996), 43(2), 105-117; Sala, Martin et al., “Synthesis of 3-(a- and b-D-arabinofuranosyl)-6-chloro-1,2,4-triazolo[4,3-b]pyridazine,” Carbohydrate Research (2003), 338(20), 2057-2066; Cucek, Karmen et al., “Synthesis of novel [1,2,4]triazolo[4,3-b]pyridazines,” ARKIVOC (Gainesville, Fla., United States) [online computer file] (2001), (5), 79-86, URL: http://www.arkat-usa.org/ark/journal/Volume2/Part3/Tisler/MT-161/MT-161.pdf; Svete, Jurij et al., “A simple one pot synthesis of 1-(s-triazolo[4,3-x]azinyl-3)-substituted polyols,” Journal of Heterocyclic Chemistry (1997), 34(4), 1115-1121; Kosary, Judit et al., “Preparation of new [1,2,4]triazolo[4,3-b]pyridazines. Part 12: Studies in the field of pyridazine compounds,” Pharmazie (1983), 38(6), 369-71; Kosary, J. et al., “Studies in the field of pyridazine compounds. II. Derivatives of [1,2,4]triazolo[4,3-b]pyridazine-3-carboxylic acid,” Acta Chimica Academiae Scientiarum Hungaricae (1980), 103(4), 405-13; Stanovnik, B. et al., “Product class 1: pyrazoles,” Science of Synthesis (2002), 12, 15-225; Vranicar, Lidija et al., “Transformation of N-(5-acetyl-6-methyl-2-oxo-2H-pyran-3-yl)benzamide with hydrazines in the presence of an acidic catalyst,” Heterocycles (2003), 61, 105-112; Bratusek, Urska et al., “Synthesis and reactivity of (Z)-3-benzoylamino-4-dimethylamino-2-oxo-3-butene. Preparation of 1-aryl- and 1-heteroaryl-substituted 4-benzoylamino-5-methyl-1H-pyrazoles,” Heterocycles (2002), 57(11), 2045-2064; Bratusek, Urska et al., “Transformation of 4-[1-(dimethylamino)ethylidene]-2-phenyl-5(4H)-oxazolone into methyl 2-(benzoylamino)-3-oxobutanoate. The synthesis of 1-substituted 4-(benzoylamino)-3-methyl-5(2H)-pyrazolones,” Journal of Heterocyclic Chemistry (1998), 35(6), 1281-1284; Vranicar, Lidija et al., “2H-Pyran-2-ones as synthons for (E)-α,β-didehydroamino acid derivatives,” Tetrahedron (1999), 55(1), 271-278.
Protein kinases are enzymatic components of the signal transduction pathways that catalyze the transfer of the terminal phosphate from ATP to the hydroxy group of tyrosine, serine and/or threonine residues of proteins. Thus, compounds that inhibit protein kinase functions are valuable tools for assessing the physiological consequences of protein kinase activation. The overexpression or inappropriate expression of normal or mutant protein kinases in mammals has been a topic of extensive study and has been demonstrated to play a significant role in the development of many diseases, including diabetes, angiogenesis, psoriasis, restenosis, ocular diseases, schizophrenia, rheumatoid arthritis, atherosclerosis, cardiovascular disease and cancer. The cardiotonic benefit of kinase inhibition has also been studied. In sum, inhibitors of protein kinases have particular utility in the treatment of human and animal disease.
The hepatocyte growth factor (HGF) (also known as scatter factor) receptor, c-Met, is a receptor tyrosine kinase that regulates cell proliferation, morphogenesis, and motility. The c-Met gene is translated into a 170 kD protein that is processed into a cell surface receptor composed of a 140 kD β transmembrane subunit and 50 kD glycosylated extra cellular a subunit.
Mutations in c-Met, over-expression of c-Met and/or HGF/SF, expression of c-Met and HGF/SF by the same cell, and overexpression and/or aberrant c-Met signaling is present in a variety of human solid tumors and is believed to participate in angiogenesis, tumor development, invasion, and metastasis.
Cell lines with uncontrolled c-Met activation, for example, are both highly invasive and metastatic. A notable difference between normal and transformed cells expressing c-Met receptor is that phosphorylation of the tyrosine kinase domain in tumor cells is often independent of the presence of ligand.
C-Met mutations/alterations have been identified in a number of human diseases, including tumors and cancers—for instance, hereditary and sporadic human papillary renal carcinomas, breast cancer, colorectal cancer, gastric carcinoma, glioma, ovarian cancer, hepatocellular carcinoma, head and neck squamous cell carcinomas, testicular carcinoma, basal cell carcinoma, liver carcinoma, sarcoma, malignant pleural mesothelioma, melanoma, multiple myeloma, osteosarcoma, pancreatic cancer, prostate cancer, synovial sarcoma, thyroid carcinoma, non-small cell lung cancer (NSCLC) and small cell lung cancer, transitional cell carcinoma of urinary bladder, testicular carcinoma, basal cell carcinoma, liver carcinoma—and leukemias, lymphomas, and myelomas—for instance, acute lymphocytic leukemia (ALL), acute myeloid leukemia (AML), acute promyelocytic leukemia (APL), chronic lymphocytic leukemia (CLL), chronic myeloid leukemia (CML), chronic neutrophilic leukemia (CNL), acute undifferentiated leukemia (AUL), anaplastic large-cell lymphoma (ALCL), prolymphocytic leukemia (PML), juvenile myelomonocyctic leukemia (JMML), adult T-cell ALL, AML with trilineage myelodysplasia (AML/TMDS), mixed lineage leukemia (MLL), myelodysplastic syndromes (MDSs), myeloproliferative disorders (MPD), multiple myeloma, (MM), myeloid sarcoma, non-Hodgkin's lymphoma and Hodgkin's disease (also called Hodgkin's lymphoma). See Maulik G, Shrikhande A, Kijima T, Ma P C, Morrison P T, Salgia R., Role of the hepatocyte growth factor receptor, c-Met, in oncogenesis and potential for therapeutic inhibition. Cytokine Growth Factor Rev. February 2002; 13(1):41-59, and cites therein: Bieche, M. H. Champeme and R. Lidereau, Infrequent mutations of the MET gene in sporadic breast tumours (letter). Int. J. Cancer 82 (1999), pp. 908-910; R. L. Camp, E. B. Rimm and D. L. Rimm, Met expression is associated with poor outcome in patients with axillary lymph node negative breast carcinoma. Cancer 86 (1999), pp. 2259-2265; L. Nakopoulou, H. Gakiopoulou, A. Keramopoulos et al., c-met tyrosine kinase receptor expression is associated with abnormal beta-catenin expression and favourable prognostic factors in invasive breast carcinoma. Histopathology 36 (2000), pp. 313-325; C. Liu, M. Park and M. S. Tsao, Over-expression of c-met proto-oncogene but not epidermal growth factor receptor or c-erbB-2 in primary human colorectal carcinomas. Oncogene. 7 (1992), pp. 181-185; K. Umeki, G. Shiota and H. Kawasaki, Clinical significance of c-met oncogene alterations in human colorectal cancer. Oncology 56 (1999), pp. 314-321; H. Kuniyasu, W. Yasui, Y. Kitadai et al., Frequent amplification of the c-met gene in scirrhous type stomach cancer. Biochem. Biophys. Res. Commun. 189 (1992), pp. 227-232; H. Kuniyasu, W. Yasui, H. Yokozaki et al., Aberrant expression of c-met mRNA in human gastric carcinomas. Int. J. Cancer 55 (1993), pp. 72-75; W. S. Park, R. R. Oh, Y. S. Kim et al., Absence of mutations in the kinase domain of the Met gene and frequent expression of Met and HGF/SF protein in primary gastric carcinomas. Apmis 108 (2000), pp. 195-200; J. H. Lee, S. U. Han, H. Cho et al., A novel germ line juxtamembrane Met mutation in human gastric cancer. Oncogene 19 (2000), pp. 4947-4953; T. Moriyama, H. Kataoka, H. Tsubouchi et al., Concomitant expression of hepatocyte growth factor (HGF), HGF activator and c-met genes in human glioma cells in vitro. FEBS Lett. 372 (1995), pp. 78-82; Y. W. Moon, R. J. Weil, S. D. Pack et al., Missense mutation of the MET gene detected in human glioma. Mod. Pathol. 13 (2000), pp. 973-977; M. Di Renzo, M. Olivero, T. Martone et al., Somatic mutations of the met oncogene are selected during metastatic spread of human HNSC carcinomas. Oncogene 19 (2000), pp. 1547-1555; K. Suzuki, N. Hayashi, Y. Yamada et al, Expression of the c-met proto-oncogene in human hepatocellular carcinoma. Hepatology 20 (1994), pp. 1231-1236; W. S. Park, S. M. Dong, S. Y. Kim et al., Somatic mutations in the kinase domain of the Met/hepatocyte growth factor receptor gene in childhood hepatocellular carcinomas. Cancer Res. 59 (1999), pp. 307-310; L. Schmidt, K. Junker, G. Weirich et al., Two North American families with hereditary papillary renal carcinoma and identical novel mutations in the MET proto-oncogene. Cancer Res. 58 (1998), pp. 1719-1722; J. Fischer, G. Palmedo, R. von Knobloch et al., Duplication and over-expression of the mutant allele of the MET proto-oncogene in multiple hereditary papillary renal cell tumours. Oncogene. 17 (1998), pp. 733-739; Z. Zhuang, W. S. Park, S. Pack et al., Trisomy 7-harbouring non-random duplication of the mutant MET allele in hereditary papillary renal carcinomas. Nat Genet 20 (1998), pp. 66-69; M. Olivero, G. Valente, A. Bardelli et al., Novel mutation in the ATP-binding site of the MET oncogene tyrosine kinase in a HPRCC family. Int. J. Cancer 82 (1999), pp. 640-643; L. Schmidt, K. Junker, N. Nakaigawa et al., Novel mutations of the MET proto-oncogene in papillary renal carcinomas. Oncogene 18 (1999), pp. 2343-2350; M. Jucker, A. Gunther, G. Gradl et al., The Met/hepatocyte growth factor receptor (HGFR) gene is over-expressed in some cases of human leukemia and lymphoma. Leuk. Res. 18 (1994), pp. 7-16; E. Tolnay, C. Kuhnen, T. Wiethege et al., Hepatocyte growth factor/scatter factor and its receptor c-Met are over-expressed and associated with an increased microvessel density in malignant pleural mesothelioma. J. Cancer Res. Clin. Oncol. 124 (1998), pp. 291-296; J. Klominek, B. Baskin, Z. Liu et al, Hepatocyte growth factor/scatter factor stimulates chemotaxis and growth of malignant mesothelioma cells through c-met receptor. Int. J. Cancer 76 (1998), pp. 240-249; Thirkettle, P. Harvey, P. S. Hasleton et al., Immunoreactivity for cadherins, HGF/SF, met, and erbB-2 in pleural malignant mesotheliomas. Histopathology 36 (2000), pp. 522-528; P. G. Natali, M. R. Nicotra, M. F. Di Renzo et al., Expression of the c-Met/HGF receptor in human melanocytic neoplasms: demonstration of the relationship to malignant melanoma tumour progression. Br. J. Cancer 68 (1993), pp. 746-750; O. Hjertner, M. L. Torgersen, C. Seidel et al., Hepatocyte growth factor (HGF) induces interleukin-11 secretion from osteoblasts: a possible role for HGF in myeloma-associated osteolytic bone disease. Blood 94 (1999), pp. 3883-3888; C. Liu and M. S. Tsao, In vitro and in vivo expression of transforming growth factor-alpha and tyrosine kinase receptors in human non-small-cell lung carcinomas. Am. J. Pathol. 142 (1993), pp. 1155-1162; M. Olivero, M. Rizzo, R. Madeddu et al., Over-expression and activation of hepatocyte growth factor/scatter factor in human non-small-cell lung carcinomas. Br J. Cancer 74 (1996), pp. 1862-1868; E. Ichimura, A. Maeshima, T. Nakajima et al, Expression of c-met/HGF receptor in human non-small cell lung carcinomas in vitro and in vivo and its prognostic significance. Jpn. J. Cancer Res. 87 (1996), pp. 1063-1069; Takanami, F. Tanana, T. Hashizume et al., Hepatocyte growth factor and c-Met/hepatocyte growth factor receptor in pulmonary adenocarcinomas: an evaluation of their expression as prognostic markers. Oncology 53 (1996), pp. 392-397; J. M. Siegfried, L. A. Weissfeld, J. D. Luketich et al., The clinical significance of hepatocyte growth factor for non-small cell lung cancer. Ann Thorac. Surg. 66 (1998), pp. 1915-1918; M. Tokunou, T. Niki, K. Eguchi et al., c-MET expression in myofibroblasts: role in autocrine activation and prognostic significance in lung adenocarcinoma. Am J. Pathol. 158 (2001), pp. 1451-1463; R. Ferracini, M. F. Di Renzo, K. Scotlandi et al., The Met/HGF receptor is over-expressed in human osteosarcomas and is activated by either a paracrine or an autocrine circuit. Oncogene 10 (1995), pp. 739-749; M. F. Di Renzo, M. Olivero, D. Katsaros et al., Over-expression of the Met/HGF receptor in ovarian cancer. Int. J. Cancer 58(1994), pp. 658-662; H. M. Sowter, A. N. Corps and S. K. Smith, Hepatocyte growth factor (HGF) in ovarian epithelial tumour fluids stimulates the migration of ovarian carcinoma cells. Int. J. Cancer 83 (1999), pp. 476-480; M. Ebert, M. Yokoyama, H. Friess et al., Co-expression of the c-met proto-oncogene and hepatocyte growth factor in human pancreatic cancer. Cancer Res. 54 (1994), pp. 5775-5778; L. L. Pisters, P. Troncoso, H. E. Zhau et al., c-met proto-oncogene expression in benign and malignant human prostate tissues. J. Urol. 154 (1995), pp. 293-298; P. A. Humphrey, X. Zhu, R. Zarnegar et al., Hepatocyte growth factor and its receptor (c-MET) in prostatic carcinoma. Am J. Pathol. 147 (1995), pp. 386-396; K. Rygaard, T. Nakamura, M. Spang-Thomsen et al., Expression of the proto-oncogenes c-met and c-kit and their ligands, hepatocyte growth factor/scatter factor and stem cell factor, in SCLC cell lines and xenografts. Br J. Cancer 67 (1993), pp. 37-46; Y. Oda, A. Sakamoto, T. Saito et al., Expression of hepatocyte growth factor (HGF)/scatter factor and its receptor c-MET correlates with poor prognosis in synovial sarcoma. Hum. Pathol 31 (2000), pp. 185-192; M. F. Di Renzo, M. Olivero, G. Serini et al., Over-expression of the c-MET/HGF receptor in human thyroid carcinomas derived from the follicular epithelium. J. Endocrinol. Invest 18 (1995), pp. 134-139; K. Gohji, M. Nomi, Y. Niitani et al., Independent prognostic value of serum hepatocyte growth factor in bladder cancer. J. Clin. Oncol. 18 (2000), pp. 2963-2971.
Because of the role of aberrant HGF/SF-Met signaling in the pathogenesis of various human cancers, inhibitors of c-Met receptor tyrosine kinase have broad applications in the treatment of cancers in which Met activity contributes to the invasive/metastatic phenotype, including those in which c-Met is not overexpressed or otherwise altered. Inhibitors of c-Met also inhibit angiogenesis and therefore are believed to have utility in the treatment of diseases associated with the formation of new vasculature, such as rheumatoid, arthritis, retinopathy. See, Michieli P, Mazzone M, Basilico C, Cavassa S, Sottile A, Naldini L, Comoglio P M. Targeting the tumor and its microenvironment by a dual-function decoy Met receptor. Cancer Cell. July 2004; 6(1):61-73.
Over-expression of c-Met is also believed to be a potentially useful predictor for the prognosis of certain diseases, such as, for example, breast cancer, non-small cell lung carcinoma, pancreatic endocrine neoplasms, prostate cancer, esophageal adenocarcinoma, colorectal cancer, salivary gland carcinoma, diffuse large B-cell lymphoma and endometrial carcinoma.
See Herrera L J, El-Hefnawy T, Queiroz de Oliveira P E, Raja S, Finkelstein S, Gooding W, Luketich J D, Godfrey T E, Hughes S J., The HGF Receptor c-Met Is Overexpressed in Esophageal Adenocarcinoma. Neoplasia. January 2005;7(1):75-84; Zeng Z, Weiser M R, D'Alessio M, Grace A, Shia J, Paty P B., Immunoblot analysis of c-Met expression in human colorectal cancer: overexpression is associated with advanced stage cancer. Clin Exp Metastasis. 2004;21(5):409-17; He Y, Peng Z, Pan X, Wang H, Ouyang Y. [Expression and correlation of c-Met and estrogen receptor in endometrial carcinomas] Sichuan Da Xue Xue Bao Yi Xue Ban. January 2003;34(1):78-9, 88 (English Abstract Only); Tsukinoki K, Yasuda M, Mori Y, Asano S, Naito H, Ota Y, Osamura R Y, Watanabe Y. Hepatocyte growth factor and c-Met immunoreactivity are associated with metastasis in high grade salivary gland carcinoma. Oncol Rep. November 2004;12(5):1017-21; Kawano R, Ohshima K, Karube K, Yamaguchi T, Kohno S, Suzumiya J, Kikuchi M, Tamura K. Prognostic significance of hepatocyte growth factor and c-MET expression in patients with diffuse large B-cell lymphoma. Br J Haematol. November 2004;127(3):305-7; Lengyel E, Prechtel D, Resau J H, Gauger K, Welk A, Lindemann K, Salanti G, Richter T, Knudsen B, Vande Woude G F, Harbeck N. C-Met overexpression in node-positive breast cancer identifies patients with poor clinical outcome independent of Her2/neu. Int J Cancer. 2005 Feb. 10; 113(4):678-82; Hansel D E, Rahman A, House M, Ashfaq R, Berg K, Yeo C J, Maitra A. Met proto-oncogene and insulin-like growth factor binding protein 3 overexpression correlates with metastatic ability in well-differentiated pancreatic endocrine neoplasms. Clin Cancer Res. 2004 Sep. 15;10(18 Pt 1):6152-8; Knudsen B S, Edlund M. Prostate cancer and the met hepatocyte growth factor receptor. Adv Cancer Res. 2004;91:31-67; D Masuya, C Huang, D Liu, T Nakashima, et al., The tumour-stromal interaction between intratumoral c-Met and stromal hepatocyte growth factor associated with tumour growth and prognosis in non-small-cell lung cancer patients. British Journal of Cancer. 2004; 90:1552-1562; Ernst Lengyel, Dieter Prechtel, James H. Resau, Katja Gauger, et al. C-Met overexpression in node-positive breast cancer identifies patients with poor clinical outcome independent of Her2/neu. Int. J. Cancer 2005; 113: 678-682.
Many strategies have been devised to attenuate aberrant Met signaling in human tumors. Some of these strategies include the use of HGF antagonists and small-molecule inhibitors. For instance, there are a number of HGF/SF antagonists or inhibitors currently in clinical development, such as Abbott (ABT-510), EntreMed (angiostatin), Kosan Biosciences (17-AAG), Amgen (AMG-102), Exelixis (XL-880 and XL-184), Pfizer (PNU-145156E), and ArQule (ARQ 197).